Differences in coagulation responses to vascular injury between uninterrupted dabigatran and apixaban: A clinical prospective randomized study.

Background: The coagulation response during vascular injury with uninterrupted administration of direct oral anticoagulants has not been elucidated.

Objective: Our aim was to evaluate differences in coagulation responses after vascular injury between uninterrupted direct thrombin inhibitor and direct factor Xa inhibitor recipients.

Methods: Patients scheduled for catheter ablation for atrial fibrillation were randomly assigned to receive dabigatran or apixaban in this prospective, randomized, comparative, parallel-group study. Venous blood was collected 3 times: 180 minutes after taking the anticoagulant on the day before the procedure, before vascular punctures of the ablation procedure, and 10-15 minutes after the start of vascular punctures.

Results: Forty-two patients were enrolled. The prothrombin fragment 1+2 level, the primary end point, was much larger after vascular puncture in the uninterrupted dabigatran recipients (median, 83 pmol/L; interquartile range, 56-133 pmol/L) than in the uninterrupted apixaban recipients (median, 1 pmol/L; interquartile range, -3 to 19 pmol/L; P < .001). Antithrombin levels decreased after vascular puncture in dabigatran recipients, and both protein C and antithrombin levels decreased after vascular puncture in apixaban recipients.

Conclusion: Unlike uninterrupted apixaban, uninterrupted dabigatran does not inhibit thrombin generation in response to vascular injury.